Passive control of microclimate in museum display cases: A lumped parameter model and experimental tests

Abstract

Abstract Inappropriate values, large and fast variations of air humidity and temperature could enhance the risks of damages to works of art and to cultural materials hosted in museums. The use of showcases as a microclimate control tool is widely accepted and ever increasing. The microclimate control of the air inside display cases relies on passive means (air-tightness, thermal insulation and inertia, adsorption capacity) or on active means (equipment to heat, cool, humidify, dehumidify the air). This paper only deals with passive type display cases. The aim has been the development and the validation of a lumped parameters model, able to simulate the air temperature and humidity behaviors inside a showcase under different conditions of the museum indoor air. The simulation model allows explicit consideration of the impact (on internal temperature and humidity) of the display case design features, such as size, material properties, air-tightness, etc., and of some other possible passive temperature and/or humidity control systems (added thermal capacity and water vapor adsorption capacity). A re-configurable freestanding showcase has been experimentally tested in a climatic test chamber under different conditions of temperature and humidity. The simulated showcase internal conditions agree well with the experimental ones. Hence, the model may be regarded as a useful simulation tool for new showcase design optimization, operation and maintenance, as well as for assessment of existing ones.